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On the prospect of other types of climate-related lawsuits being successful: “I think that some other areas where litigation will be very common will be challenges to proposed fossil fuel projects, whether it’s mines, or pipelines, or power plants, or refineries. I think we’ll see more of that kind of litigation, we’ve already seen a lot of it over the years, some of it quite successful.”

On Trump’s threat to pull the US out of the Paris Agreement: “If the US fails to meet the pledges, which it will under President Trump, there’s not really legal recourse that other countries or individuals have as part of the international system. Now in terms of withdrawing from Paris itself…if a country withdraws prematurely, there are no penalties or sanctions.”

On why so many Republicans reject climate science: “It’s partly because of an ideology against government in general, and if you believe in climate change, and that it’s caused largely by human activities, and that we need to do something about it, that necessarily leads to government action. And, if you don’t want government action, then one psychological mechanism is to deny there’s a problem that requires government action.”

On why so many Republicans reject climate science, continued: “This denial of climate science is a deeply disturbing phenomenon…I think there are others, on the Republican side in Congress who deep down believe in the science of climate change, but they know they can get into political trouble if they say that publicly.”

On signs of positivity – and negativity – regarding action on climate change: “Renewables are becoming quite competitive with fossil fuels. And we also know that renewables are a tremendous source of employment growth…On the bad side, tragically, we’re going to see more weather disasters. And more people lose their lives as a result of extreme events that were worsened by climate change.”

On negative emissions technologies: “Engaging in that kind of effort to remove carbon dioxide from the atmosphere is not globally harmful and doesn’t pose lots of threats to international governments.”

On geoengineering: “We need an international governance mechanism to globally make decision on whether it’s legitimate to engage in that kind of activity…I formerly thought that that kind of research was a terrible idea, that it was too risky. But the world has fallen so far behind where it needs to be in reducing greenhouse gas emissions that we may get to a desperate point that we need to try something along those lines.”

Carbon Brief: On the broadest level, what does the election of Donald Trump mean for action on climate change?

Michael Gerrard: It means that the United States’ policy on climate change is completely reversing. Donald Trump took the position during the campaign that he believed that climate change was a hoax. He also said that we should maximise the extraction and use of fossil fuels in the United States. And so President Trump is doing everything he can to undo the Obama legacy on climate change. In short, it’s been catastrophic.

CB: So, it looks like Trump will both rely and possibly be thwarted by US legal system when it comes to driving through his anti-climate agenda. What do you think are the key battlegrounds? For example, how significant do you think the supreme court and his pick will be over the term of his presidency?

MG: Well, I think the supreme court will be extremely important for a lot of public policy issues. But not so much with climate change because the primary legal disputes over climate change will only partly be the sort of case that could make it up to the supreme court. I think that most of the action is going to be efforts by the administration to roll back the existing regulations that exist. That will take some years to do it – they’ll all be challenged – but, meanwhile, some of the regulations will not be in effect. The clean power plan is one example and we can get into the details of that. For others, they’ll be slowed down; Trump will be slowed down by litigation. However, there’s going to be a lot of litigation at the state level. I think that’ll also be a key area of dispute.

CB: So, on the clean power plan, Trump seems determined to undo it, particularly with his recent executive order. And he’s asking the US court of appeals district of Columbia circuit to hold its own legal review. Do you think he will be successful in this kind of attack on the clean power plan?

MG: Ultimately, yes, I’m sorry to say. The clean power plan has been stayed by the supreme court, so it’s not now in effect and won’t go into effect until the supreme court finally gets the case and has disposed of it. Meanwhile, Trump has made it very clear that he… his EPA is not going to enforce the clean power plan. So they have to go through a fairly elaborate process to repeal it, but I think, ultimately, they’re probably going to be successful in repealing it. There’ll be litigation over it. There will, in particular, be challenges saying that they need to replace it with something else in view of prior supreme court precedent. But that all will take several years.

CB: How legally secure is the EPA’s endangerment finding that carbon dioxide should be treated as a pollutant?

MG: That I feel pretty good about. There has been a lot of pressure on Scott Pruitt, the administrator of the EPA, to start the process to revoke it. But I think he has, wisely so far, decided not to do that because trying to revoke it would fly in the face of large volumes of very solid scientific evidence. The endangerment finding was solidly supported by science when it was first issued in 2009. The science since then has become even stronger, so I think that it would be a bad tactical mistake on the part of the administration to try to revoke the endangerment finding. It doesn’t now look like they’re going to try to do that.

CB: So, equally, Trump has targeted the so-called social cost of carbon. How might he attack that from a legal perspective?

MG: So, the social cost of carbon is a metric that has been used by administrative agencies within the federal government to assess the climate change impact of various regulatory actions. It’s not a part of any statute or regulation, so it was purely a matter of administrative action by the federal government. So what the federal government does through executive action, it can undo through executive action. However, there’s underlying case law suggesting that something of that sort ought to be used. So I think a frontal assault on trying to repeal the social costs of carbon would be very difficult. But, instead, we’ll see litigation challenging particular actions the federal government takes, that did not consider the impact of climate change. And that will be litigated, I think, probably in multiple law suits.

CB: How might, say, something like the Dodd-Frank law be used to force companies to be more transparent about their fossil fuel assets and their responsibilities with regard to action on climate?

MG: I don’t think the Dodd-Frank act has much bearing on it. It’s really aimed at financial fraud. What is more relevant is the underlying securities laws that have long required companies to disclose factors that are material to their earnings or their value. In 2010, the US securities and exchange commission [SEC] issued a guidance document that specified how climate change should be considered and disclosed in the context of securities disclosure. The SEC, under President Obama, although it issued that guidance, has done very little to enforce it. They’ve had much, or many other things relating to the financial industry and so forth that they’ve concentrated on.

It would not be surprising at all to see the SEC under President Trump revoke that guidance. But at the same time there’s the underlying law that requires disclosure of material risk. I think the more productive use of the securities laws is being done at the state level. Some states, including New York, have what are called blue sky laws – state securities regulation laws. And the New York attorney general is now investigating Exxon Mobil to determine whether it failed to disclose certain material risks to their company as a result of climate change and its regulation. So when you have a vigorous state attorney general, as we do in New York and some other states, I think we’ll see much more action than we’ve seen at the federal level with the SEC. Certainly for the next four years we’re not going to see much action by the SEC, so I’m looking mostly to the states on that one.

CB: You just raised the so-called “ExxonKnew” proceedings. More widely, what are your views on that specific case? As you mentioned, whereby a number of state attorney generals are seeking information from Exxon on how much it knew about climate science in earlier decades. What kind of precedent might that be setting in the years ahead?

MG: We don’t know yet. Exxon has turned over quite a few documents to the New York state attorney general and the attorney general is seeking more. We don’t know what’s in those documents. If the documents show that there was information that was within Exxon’s possession that was not open to the public and that had a material effect on the earnings or value of Exxon, then the attorney general may go after them for securities fraud. But we don’t know what the information will reveal. The mere fact that Exxon had a lot of information years ago about climate change does not in itself form a basis for an action. Because there was a lot of public information at that time available to investors. But if there was information that Exxon itself had, I think that that could have an impact.

I think, more generally, the investigation by the New York attorney general against Exxon and its prior investigations of Peabody has made some big companies more careful in their filings, more aware that they could have difficulties if they don’t fully disclose their impacts.

CB: The Children’s Trust is currently pursuing a case against the government arguing it “has violated the youngest generation’s constitutional rights to life, liberty, and property, as well as failed to protect essential public trust resources”. What prospects does it have at succeeding and what wider impact might a ruling either way have?

MG: Our Children’s Trust, this group in Oregon, has brought or organised quite a few lawsuits around the United States and several other countries. Most of the lawsuits were dismissed, but the case in Oregon is continuing, and the federal district judge in Oregon denied a motion to dismiss the lawsuit and found that there might be a constitutional obligation on the part of the federal government to protect the climate to make sure that we don’t have an unhealthy climate for future generations. That is really very unusual and unprecedented decision from the United States to have a judge say that. It’s gotten a lot of attention. Ordinarily that decision could not yet be appealed, because it’s not the final disposition of the case.

And, ordinarily, the next steps would be a discovery where documents are disclosed and, perhaps, depositions are taken and, ultimately, a trial. But the federal government, under President Trump, has now asked for the right to appeal, and they’ve been joined by the American Petroleum Institute and some other industry trade associations that also don’t like the lawsuit going forward. We’ll see if they’re able to appeal it to the court of appeals. Meanwhile, the case has brought a lot of attention to these climate change issues. It’s frankly difficult to imagine that, ultimately, if this case makes it’s way to the supreme court, I do not believe that there will be a majority of the justices on the court who would uphold the conclusion of the district court. So I don’t know how long lived that particular ruling will be. But, while it’s out there, it’s inspiring some other litigation in the United States and elsewhere.

We’re also seeing the phenomenon of several decisions emerging from countries around the world based on theories of either the national constitutions of those countries, or human rights theories, or other over-arching legal theories apart from specific statutes on air pollution or climate change. We’ve seen decision from the Netherlands, Pakistan, Austria, and very recently from South Africa. So these cases are popping up around the world as judges see that the administrative structures are not doing what they need to do to protect their populations against climate change. And more lawsuits have been brought, and one recently in Norway, one in Belgium, some others around the world. It’s a very interesting phenomenon.

CB: On that point, you’ve mentioned a few examples there in the Netherlands, Pakistan, South Africa, for example. How else might climate litigation be used in coming years? I’m thinking five, ten years and beyond, both in the US and abroad, to drive forward action on climate change. For example, pinning liability on polluters for rising sea levels affecting low-lying island states…

MG: So far, there’s been no success in any of the lawsuits that have tried to make fossil fuel companies or motor vehicle manufacturers or others liable for climate change. There were a few attempts in the United States, which were all dismissed. It’s possible that some small island state, or other country, will bring a lawsuit in its own courts, under its own law, and see what happens with that. I think that some other areas where litigation will be very common will be challenges to proposed fossil fuel projects, whether it’s mines, or pipelines, or power plants, or refineries. I think we’ll see more of that kind of litigation, we’ve already seen a lot of it over the years, some of it quite successful. Another area where I think we will begin to see lawsuits is lawsuits against governments and corporations that failed to prepare for climate change.

So, for example, if a building or a bridge or something like that is destroyed, or severely damaged in a storm, and the magnitude of the storm could’ve been and should’ve been foreseen before the building was built, there may be claims against architects, engineers, builders, for not reflecting these foreseeable risks in their designs. We’ve already seen some litigation against municipalities for not having adequate drainage and stormwater protection systems to prepare for the flooding that could be anticipated. None of these cases has gotten very far, but I think we’ll see more of that.

I think that that kind of litigation will have a couple of effects. One is that it will induce more preparedness, which is a good thing because we know that weather conditions are going to become more extreme in the years to come. So it’s very important that everyone try to prepare for that. Secondly, it, ultimately, could have a political impact to the extent that it forces the top executives of companies and government agencies and so forth to think systematically about the effect that climate change will have on their own enterprises. I think that will raise the consciousness and concern about climate change at some very high levels.

CB: How do you bring something such as the science of climate attribution…how does a lawyer bring in the kind of science of attributing a certain weather event, or sea level rise, into a courtroom? That’s presumably a big challenge, isn’t it, in terms of climate litigation?

MG: Well, actually, all the lawsuits that have been brought, where climate science was an issue and where the courts actually dealt with the climate science as opposed to finding a procedural way to not deal with it, have upheld climate science. Starting with the US supreme court’s decision that was issued exactly 10 years ago, the Massachusetts vs the EPA decision acknowledged climate science. And there have been several decisions since then. So the underlying reality of climate science has really not been successful disputed in any court in the world. Attribution of specific events to climate change is more difficult, but it could arise in the context of whether a given kind of event was foreseeable and should’ve been prepared for.

A further level of attribution that some are seeking is to say that particular companies are responsible for a certain percentage of greenhouse gas emissions. That has not succeeded anywhere, and there’s now a petition pending before the Philippines human rights commission that asserts that and is trying to establish that. But, otherwise, there was a case in Germany that tried to assert that and it was dismissed as being too remote. That’s a very, very challenging prospect, particularly since we all know that climate change is the result of the cumulative emissions of millions of emitting sources over more than a century. And so attributing climate impacts to particular companies is very difficult.

CB: What other legal obligations does the US have to the Paris agreement which Obama ratified last year? And what legal options does Trump now have to withdraw from the international agreement, as he’s previously pledged to do?

MG: Most of the Paris Agreement is voluntary. There are mandatory provisions on greenhouse gas emissions reporting and that kind of thing. And the US has been doing that for decades without difficulty, but the emission reduction pledges that are the heart of the protocol are written in voluntary terms. They’re not enforceable. And so if the US fails to meet the pledges, which it will under President Trump, there’s not really legal recourse that other countries or individuals have as part of the international system. Now in terms of withdrawing from Paris itself, the terms of the Paris Agreement provide that, basically, four years advanced notice needs to be given to withdraw lawfully. However, if a country withdraws prematurely, there are no penalties or sanctions.

President Trump has shown disregard for international law in a number of respects; his views on torture and on seizing the oil in Iraq, and various other things. He doesn’t seem to care about international laws so he probably wouldn’t care about the particular withdrawal provisions of the Paris Agreement. Having said that, we don’t know whether the US will withdraw. It appears that there’s a dispute within his administration about whether the US should stay in Paris and have a seat at the negotiating table, or should withdraw. So we don’t know how that’s going to play out.

CB: In the Paris Agreement, particularly with Article 4, as you already indicated, it’s a kind of – regarding the pledge of each nation – it’s a kind of voluntary wording. So it says that a country can revise its pledge “at any time…with a view to raising ambition”. So, as you’ve suggested, Trump can effectively just ignore that if he wanted to stay within Paris, but downgrade the US pledge in terms of emission reduction out to 2025. It’s, effectively, a pretty easy ride that he can do that…

MG: That’s right, it was clearly the intent of the negotiators to encourage ever-increasing ambition. And there is a ratchet mechanism within the Paris agreement that calls for that. But it’s not mandatory. And if the US decides to make its pledge less ambitious, there are no sanctions that can be brought against the US for doing that.

CB: What impact do you think Trump’s proposed budget for 2018 onwards… in the fact that he said that he will eliminate all US funding to the Green Climate Fund, to the Climate Investment Fund? You know that international climate pledge within the Paris Agreement, with this ambition of reaching $100 billion a year by 2020, etc. Is that the thing that’s going to have the biggest kind of wrecking-ball impact diplomatically, in terms of what Trump could do to the Paris Agreement?

MG: So, of course, this is not the final budget. It’s the budget that President Trump submitted to Congress. And, ultimately, Congress will have to decide. It’s very common that Congress makes significant changes to the president’s budget proposal. Having said that, there’s not a lot of support in Congress for international aid on climate issues, given the Republican majorities in both the House and the Senate. If the US carries through on President Trump’s promise not to contribute to the Green Climate Fund or these other efforts, first place, it will have a very negative impact on the countries that would’ve received the aid, that really need the money. Whether it will induce other countries to back down as well, we don’t know yet. We’re not sure how all of this will play out. It does seem that the US has ceded leadership in international climate change issues to China, which is ironic on many different fronts. But whether that will, ultimately, lead to less international climate action and climate assistance, it’s really too early to tell.

CB: Please can you explain to our non-American readers, why Republicans seem to have such an extreme reaction to climate science and the resulting climate policies?

MG: Well, that’s a fairly recent phenomenon. In 2008, the presidential election was between the Democrat senator Barack Obama and the Republican senator John McCain. And both of them favoured action on climate change, and favoured the enactment of a cap-and-trade programme. It’s really since 2008 that climate change has become such a partisan issue in the United States. It’s partly because of an ideology against government in general, and if you believe in climate change, and that it’s caused largely by human activities, and that we need to do something about it, that necessarily leads to government action. And, if you don’t want government action, then one psychological mechanism is to deny there’s a problem that requires government action.

So that’s one reason. Another reason is that the fossil-fuel companies have been major campaign contributors and lobbyists. And the US supreme court, several years ago, issued some decisions that relaxed the constraints on that kind of political contribution. There are a number of very wealthy donors who have given a lot of money to politicians, donors who don’t want any regulation of climate change. And there are donors who have gone so far as to indicate to a politician, particularly a member of Congress who supports climate action but is a Republican, that they will primary them. Which means they’ll put up candidates to oppose them in their Republican primary, which is frightening to a lot of politicians.

So [it’s] a combination of a sort of anti-government view, that the government shouldn’t be doing anything and shouldn’t be supervising people. And the support from the fossil-fuel industry and the reality of the loss of jobs in coal mining and some other areas of the country have all combined to help make this a very partisan issue. Which is an extremely unfortunate development. Beginning in 1970, environmental protection has been a bipartisan issue. The first environment statutes in the US were, of the modern era, were passed overwhelmingly by Congress and signed by a Republican president, Richard Nixon. So it’s very unfortunate that we now have this partisan divide.

CB: It’s one thing having opposition or alternative views on the policy response. But it seems another level to actually be in the kind of Lamar Smith position, where you’re actually leading a kind of war on science, it seems from the outside; actually going after the scientists in a way like a witch-hunt type of scenario. That seems to be beyond what you see in most other countries where there is debate about what the energy policy should and shouldn’t be of that country, etc, etc. But it seems that there’s a particular issue about going hard after the science…

MG: Well, there’s a tradition in the United States of significant segments of the population not being keen on science; 40-45% of the American public does not believe in evolution. Gallop has been polling that for years. And so that’s largely based on religious views and there are people in the United States who believe that Man can’t possibly be that powerful to interfere with God’s creation in this way. And, therefore, how could we possibly be interfering with the climate? This denial of climate science is a deeply disturbing phenomenon, but, as you say, it has happened and there are some in Congress who hold that view, including Lamar Smith, the chairman of the House science committee, ironically enough. I think there are others, on the Republican side in Congress who deep down believe in the science of climate change, but they know they can get into political trouble if they say that publicly. But it’s difficult to advocate strong action on climate change to someone who just doesn’t believe in the underlying science. That’s one of the major problems.

CB: What role in all that do you think the media in the US has played?

MG: I think the media in the US have played a very negative role. As is their right under the first amendment, there’s nothing illegal about it. But for many years they felt the necessity of acting as if there were two legitimate sides to the argument. And for every climate scientist, quoting a climate denier. I think we’ve seen less of that in the last few years. I think some of the media are no longer doing that. And yet there are some outlets like Fox News – which is beloved by Republicans and vice versa – that continue to spout climate denial. The Wall Street Journal editorial page is another prime source of that kind of false scientific information. And we have specialised cable channels and websites and so forth that go to much narrower audiences, but are persuasive to their audiences that spout all kinds of climate denial. The growth of online communication, social media, have made it much easier for those who are inclined to deny climate science and many other facts, to find outlets that cater to their views.

CB: In your view, what’s the way out of this? It feels like we’re in a particular moment now, post Obama, in the early days of the Trump administration…where do you see, how do you see this playing out in the US and internationally over, say, the rest of the Trump term, but beyond that?

MG: There’s some good things and there’s some bad things. Now, on the good side, the cost of renewable energy is very rapidly declining. The cost of solar cells has plummeted to a tiny fraction of what it was just a few years ago. Wind is becoming much more economical, we’re seeing a lot of developments with storage so that the intermittency of solar and wind aren’t such a problem. So renewables are becoming quite competitive with fossil fuels. And we also know that renewables are a tremendous source of employment growth. One of the fastest-growing occupational categories in the United States is wind-turbine technician. So I think that many people will begin to see the tremendous economic advantages of going with renewables. And, for one thing, when you have your solar cell or your wind turbine, you don’t have to be paying money for fuel anymore. And there are, ultimately, a lot of monetary savings to consumers. So that’s on the good side.

On the bad side, tragically, we’re going to see more weather disasters. And more people lose their lives as a result of extreme events that were worsened by climate change. And when that happens, it tends to increase consciousness. There have been two major events in the United States along those lines in recent years, Hurricane Katrina, and Hurricane Sandy. Both of which certainly increased consciousness of these issues, although not enough. We will inevitably see more of those, and that may have an effect on public opinion. The modern environmental movement in the US really took off in 1970 and one of the things that people noticed is that rivers were catching on fire because they had so much pollution. And that the air in some cities was very unhealthy, so seeing the negative impacts does have an effect on public opinion. One negative impact that becomes very apparent is extreme heat. We’re seeing much more incidents of heat waves and it’s really heat waves that are the largest single source of mortality in cities owing directly from climate change. And as we see more of that, that will also make people more conscious.

CB: Finally, you talked about some of those negative impacts… from a lawyer’s point of view, how do you see in the years and probably decades ahead the issue of something like a single nation going down the geoengineering road? Or negative emissions? Or there’s been various kind of sci-fi technologies being proposed, very little of it being actually tested at commercial scale? But there might come a point where a company, a rich individual, a country, or even a group of countries decide to do something unilaterally to try and arrest emissions. Or take CO2 out of the atmosphere? What do you see as the challenges of that?

MG: We have to distinguish between removing the carbon dioxide from the atmosphere and trying to engage in the geoengineering that holds back some of the sunlight. Removing the carbon dioxide from the atmosphere itself is benign. And the views tend to be local: if they have impacts they tend to be local impacts, the global impacts are good. And so there are a lot of difficulties figuring out the best technology, how much land does it require, who’s going to pay for it, all of that. But engaging in that kind of effort to remove carbon dioxide from the atmosphere is not globally harmful and doesn’t pose lots of threats to international governments.

On the other hand, doing things like shooting aerosols into the atmosphere to try to restrict some of the Sun has global impacts, and many people are worried about that. And it is entirely plausible to have a scenario where a country decides that it wants to do it on its own. Or an extremely rich individual and others are unhappy with that. That’s why we need an international governance mechanism to globally make decision on whether it’s legitimate to engage in that kind of activity. And to take action if someone engages in that activity without the necessary international authorisation. Informal talks on that and conferences are happening now. It is not yet on the formal agenda of any formal international bodies, but that may change in the years to come. It may well be that the climate conditions have become so desperate that it could be rational to try to engage in some of that, but we need a process to decide that. Meanwhile, there are proposals for some research to see whether it would work, how it would be done.

I formerly thought that that kind of research was a terrible idea, that it was too risky. But the world has fallen so far behind where it needs to be in reducing greenhouse gas emissions that we may get to a desperate point that we need to try something along those lines. And that would need to be preceded by research to figure out physically whether it would work and try to see what side effects it would have. So I think it’s very important that international governance mechanism be developed, both for the research and, ultimately perhaps, for the deployment of this.

CB: Do you think, in terms of that international mechanism, we might foresee a day where we have something like at the moment we have a international court of…you know that would prosecute genocide or human rights abuses? Could you see a kind of ecocide, or an environmental crime, that dealt with [this] on an international level and being part of the kind of enforcement stick behind that?

MG: Well, it’s much more difficult to impose criminal penalties than civil penalties. And so I think first we could see a regime that says what’s lawful is a matter of international law or not. And some kinds of sanctions like trade sanctions that could be imposed. I think any kind of criminal penalties are much more remote, particularly since, under the system of international law, a country is not subject to an international tribunal, unless it has consented to the jurisdiction of that tribunal. And it’s hard to envision a major country consenting to criminal jurisdiction. The US has not agreed to join the international criminal court for example. So I think I’d start out with looking at civil remedies.

CB: Great, fantastic, thank you very much.

MG: Thank you.

This interview was conducted by Leo Hickman on 4 April 2017 at the Columbia Law School in New York.